My fade coroutine won't work without an empty OnGUI method.

Hi everyone,

I noticed something interesting today. I couldn't figure out why my fade coroutine would sometimes work and sometimes not.

My FadeControl.cs is subscribed to a state change event, and fires off a coroutine when the state changes. Interestingly, the fade is aligned to the center of the screen instead of the corner of the screen if I do not include an empty "void OnGUI(){}" at the end of my cs file.

Subscribe to Event on Enable:

     private void OnEnable()
     {
         StateManager.StateChanged += DoFade;
     }

Execute Coroutine:

     private void DoFade(SceneState e)
     {
         StartCoroutine(FullFade());
     }

Do Fade:

     private IEnumerator FullFade()
     {
         float elapsedTime = 0.0f;
         while (elapsedTime < fadeTime)
         {
             yield return new WaitForEndOfFrame();
             elapsedTime += Time.deltaTime;
             Color newColor = GUI.color;
             newColor.a = Mathf.Clamp01(elapsedTime / fadeTime);
             GUI.color = newColor;
 
             GUI.depth = drawDepth;
 
             GUI.DrawTexture(new Rect(0, 0, Screen.width, Screen.height), fadeTexture);
         }
         elapsedTime = 0.0f;
         while (elapsedTime < fadeTime)
         {
             yield return new WaitForEndOfFrame();
             elapsedTime += Time.deltaTime;
             Color newColor = GUI.color;
             newColor.a = 1.0f - Mathf.Clamp01(elapsedTime / fadeTime);
             GUI.color = newColor;
 
             GUI.depth = drawDepth;
 
             GUI.DrawTexture(new Rect(0, 0, Screen.width, Screen.height), fadeTexture);
         }
     }

Again, this does not cover the whole screen unless I include the following at the end of my script. (Completely empty function:)

 private void OnGUI(){}